Recently, a measurement system using a camera is broadly utilized. However, in order to accurately measure, a calibration process is necessary with respect to the camera. Usually, in the case of a camera calibration, twelve parameters in the equation (14) have to be determined in a projection matrix 3×4) in the item [No. 7].
In the calibration method utilized by Z. Zhang (Not Patent Document 2) described in OenCV (Not Patent Document 1), it is necessary to determined nine interior parameters (four calibration parameters in a camera and five distortion correction parameters) in a camera. Further, it is also necessary to determine six exterior parameters (three translation parameters and three rotational parameters as a camera position calibration) with respect to the camera.    Patent Document 1 (CALIBRATING DEVICE FOR CALIBRATION AND MEASUREMENT SYSTEM COMPRISING CALIBRATION DEVICE) describes the following Patent Documents in which a calibration jig is described.    Patent Document 2: GNIFICATION CALIBRATION PLATE FOR IMAGE PROCESSING/MEASURING SYSTEM    Patent Document 3: GAUGE, SIZE CALIBRATING DEVICE USING THE GAUGE, AND SIZE CALIBRATING METHOD    Patent Document 4: CALIBRATION DEVICE    Patent Document 5: CALIBRATION JIG AND METHOD FOR IMAGE RECOGNITION DEVICE    Patent Document 6: DEVICE AND METHOD FOR CALCULATING REFERENCE POINT OF TARGET FOR PHOTOGRAMMETRY, AND RECORDING MEDIUM STORED WITH PROGRAM FOR CALCULATING REFERENCE POINT OF TARGET FOR PHOTOGRAMMETRY
In addition except the above Patent Documents, the following Patent Documents describe a calibration method using a camera for measuring.    Patent Document 7: CAMERA CALIBRATION METHOD FOR CAMERA MEASUREMENT OF PLANAR SUBJECT AND MEASURING DEVICE APPLYING SAME    Patent Document 8: CALIBRATING DEVICE FOR CALIBRATION AND MEASUREMENT SYSTEM COMPRISING CALIBRATION DEVICE    Patent Document 9: CALIBRATION METHOD AND CALIBRATION DEVICE    Patent Document 10: METHOD FOR CALIBRATING ROBOT AND ROBOT CALIBRATION DEVICE    Patent Documents 11 and 12: SETTING METHOD FOR PERPENDICULARITY, DISTANCE, AND ROTATION ANGLE OF HAND EYE